Substantial Earthquake in Costa Rica.

On Wednesday 5 September 2012, slightly after 8.40 am local time (slightly after 2.40 pm GMT), the Costa Rican province of Guanacaste suffered an Earthquake measured by the United States Geological Survey as a Magnitude 7.6 quake at a depth of 40.8 km. This is reported to have caused considerable damage to buildings, and while the level of injuries reported has on the whole been light so far, two people are reported to have died of heart attacks triggered by the quake, and it is quite possible that more deaths or serious injuries may emerge. A tsunami warning was initially released by the NOAA Pacific Tsunami Warning Center, but this has now been removed. 

Map showing the areas which suffered the most severe shaking during the 5 September 2012 Earthquake. Damage to buildings is quite likely inside the areas outlines in green and (particularly) yellow. USGS.

Costa Rica lies on the southern margin of the Caribbean Plate; to the south of the country the Cocos Plate, which underlies part of the eastern Pacific Ocean) is being subducted under the Middle American Trench, passing under Central America as it sinks into the Earth's interior. This is not a smooth process, and the plates often stick together until the pressure builds up enough to force them to shift suddenly, causing Earthquakes. As the Cocos Plate sinks deeper if is partially melted by the friction and the heat of the Earth's interior. Some of the melted material then rises up through the overlying Caribbean Plate, fueling the volcanoes of Central America.

Diagram showing the passage of the Cocos Plate beneath Costa Rica (not to scale). Carleton College.

See also Large Earthquake off the south coast of El Salvador, Earthquake swarm strikes southern California, Seismic activity on Mount Cumbal, Colombia, Strong Earthquake to the south of Panama and Earthquakes on Sciency Thoughts YouTube.

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New species of Ginglymodian Fish from the Late Jurassic of northeast Thailand.

The Ginglymodians are a group of primitive Ray-Finned Fish, which includes the modern Gars but which was far more diverse in the Mesozoic.

In a forthcoming paper in the journal Acta Palaeontologica Polonica, a team of Palaeontologists led by Uthumporn Deesri of the Department of Biology at the Faculty of Science at Mahasarakham University describe a new species of Ginglymodian Fish from the (probably) Late Jurassic lower Phu Kradung Formation in Kalasin Province, Thailand.

The new species is placed in the pre-existing genus Isanichthys, and given the specific name lertboosi in honour of Lertboos Gongtong, former chief of Kam Muang District. It is an 800 mm Ginglymodian Fish described from a single fairly complete specimen and three partial skulls. Isanichthys lertboosi has an ornate skull with heavy jaws and extremely variable dentition, which suggests that the specimens may in fact represent more than one species.

The more-or-less complete specimen of Isanichthys lertboosi. Deesri et al. (2012).

Detail of the skull of (top) the complete specimen of Isanichthys lertboosi and (middle and bottom) two other specimens refered to the species. Note the variation in jaw morphology. Deesri et al. (2012).

See also New species of Sleeper Gobie from the Early Miocene of Otago, New Zealand, A novel Coelacanth from the Early Triassic of British Columbia, An early Ray-Finned fish from the Middle Triassic Luoping Biota of Yunnan Province, China, Live birth in a Middle Triassic Coelacanth and Boney Fish on Sciency Thoughts YouTube.

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Five new species of Snout Moth from China.

Snout Moths are one of the larger groups of Lepidopterans (Butterflies and Moths), with over 6000 described species known from across the globe. Most of these are small and inconspicuous, and generally ignored by humans, though the larval forms of some species are considered to be pests, since they consume dried food products.

In a paper published in the journal ZooKeys on 7 August 2012, Yongling Sun of the Department of Biology at Dezhou University and Houhun Li of the College of Life Sciences at Nankai University describe five new species of Snout Moths in the widespread and species-numerous genus Endotricha, and in addition describe the females of three species previously known only from male specimens.

The first new species described is named Endotricha dentiprocessa, where dentiprocessa means 'toothed process', in reference to the genital structure of the Moth. The species is described from two male and two female specimens, all collected in 2008 from Qinmu Village in Yongfu County in the Guangxi Zhuang Autonomous Region. Endotricha dentiprocessa is a small black, white and brown moth with a wingspan of 17.0−18.5 mm.

Endotricha dentiprocessa. Female specimen. Sun & Li (2012).

The second new species is named Endotricha unicolor, where unicolor means single-coloured, a reference to the unpatterned rear wing. The species is named from one male and female specimens collected in Millen and Linzhi Counties in the Xizang (Tibet) Autonomous Region, at altitudes of between 2980 and 3065 m. Endotricha unicolor is a yellowish-brown Moth with a 20 mm wingspan.

Endotricha unicolor. (Top) Male. (Bottom) Female. Sun & Li (2012).

The third new species described is named Endotricha shafferi, in honour of the late Michael Shaffer, an entomologist at the British Museum of Natural History. The species is named from One male and two female specimens from the Yinsha Protection Station in Jinxiu County in the Guangxi Zhuang Autonomous Region. Endotricha shafferi is a black and yellow Moth with a 21 mm wingspan.

Endotricha shafferi. Female specimen. Sun & Li (2012).

The fourth new species is named Endotricha convexa, refering to the shape of the forewing. The species is described on the basis of three male and one female specimens from Yinggeling and Mount Wuzhi in Hainan Province. Endotricha convexa is a brown and yellow moth with purple markings on its wings and a wingspan of 20-22 mm. 

Endotricha convexa. (Top) Male. (Bottom) Female. Sun & Li (2012).

The fifth new species described is named Endotricha whalleyi, in honour of the late Paul Whalley, a noted entomologist. The species is described from two male specimens from Hanmi in Mêdog County in the Xizang (Tibet) Autonomous Region. Endotricha whalleyi is a brown moth with a 16 mm wingspan.

Endotricha whalleyi. Male specimen. Sun & Li (2012).

The first of the three species to have its female described for the first time is Endotricha hoenei, the male of which was described in 1963 by Paul Whalley, from Guangdong Province. Sun and Li detail five new male and 19 female specimens from Fujian and Guangxi Provinces. The female is a yellow and brown Moth with a 19-21 mm wingspan.

Endotricha hoenei. Female specimen. Sun & Li (2012).

The second species to have its female described for the first time is Endotricha luteogrisalis, originally described in 1896 from a male specimen from Bhutan. Sun and Li describe five new male and twelve female specimens from Fujian and Hainan Provinces. The female of Endotricha luteogrisalis is a brown and yellow Moth with a 16.5-20 mm wingspan.

Endotricha luteogrisalis. Female specimen. Sun & Li (2012).

The final species to have its female described for the first time is Endotricha simipunicea, originally described in 2005 from a male specimen from Zhejiang Province. Sun and Li describe eight new male specimens and three female specimens from Fujian and Guizhou Provinces. The female of Endotricha simipunicea is a red and yellow Moth with a 13.5-15 mm wingspan.

Endotricha simipunicea. Female specimen. Sun & Li (2012).

See also New Tiger Moths discovered in east Asia, New species of Leaf-Mining Moth from northern Chile and New species of moth from Yunnan Province.

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Earthquake in Cheshire.

On Sunday 2 August 2012, slightly after 6.05 pm British Summertime (slightly after 5.05 pm GMT), the British Geological Survey recorded a small Earthquake 8 km beneath the Cheshire village of Ollerton, roughly 16 km west of Macclesfield. The quake was recorded as measuring 0.7 on the Richter Scale, far to small to have caused any damage or injuries, and probably to small to have been noticed.

Map showing the location of the 2 August 2012 Earthquake. BGS.

As a rough rule of thumb Earthquakes become more common in Great Britain as you move further north and west, making Cheshire one of England's more quake-prone counties. The precise cause of quakes in the UK can be hard to determine, as the country is a long way from any active plate margin, but is subject to tectonic stresses from a number of sources. Most quakes probably cannot be attributed to a single source, but rather to a combination of stresses from a number of sources.

Britain, along with the rest of Eurasia, is being pushed to the east by the expansion of the Atlantic Ocean, and to the north by the impact of Africa into Europe from the south. It is also subject to stresss caused by smaller expansion centers beneath the North Sea, the Rhine Valley and the Bay of Biscay. In addition the country is still suffering the effects of glacial rebound. Until about 10 000 years ago much of the north of Britain was covered by a layer of glacial ice hundreds of meters thick, which pushed the rocks of the British lithosphere down into the underlying mantle. This ice has now gone, and the rocks are slowly sprining back up, causing the occational Earthquake in the process.

Witness reports of Earthquakes help geologists to understand the processes and structures that cause them. If you felt this quake you can report it to the BGS here; they would also be interested in hearing from people in the area who did not feel the quake, which is also useful information.

See also Earthquake in Nottinghamshire, Earthquake near Worksop in northern Nottinghamshire, Earthquake in Nottinghamshire, England, Earthquake in South Yorkshire and Earthquakes on Sciency Thoughts YouTube.

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Large Earthquake to the south of East Java.

On Tuesday 4 September 2012, slightly after 2.20 am local time (slightly after 6.20 pm on Monday 3 August, GMT), a large Earthquake occurred roughly 220 km south of East Java, according to the United States Geological Survey, who measured the quake as 6.4 on the Richter Scale, at a depth of 8.8 km. This is a large, shallow Earthquake which would potentially be very dangerous closer to land, but is unlikely to present any threat this far from land, and will probably only have been felt at the very southern tip of East Java and possibly Bali. It is not thought likly that the quake will have caused a tsunami.

Map showing the location of the 4 September 2012 Earthquake and the areas that will have suffered the worst shaking. The outermost circle, which just touches the south of East Java and Bali, will only have suffered light shaking. USGS.

Java and Bali are located on the southen edge of the Sunda Plate, close to its margin with the Australian Plate, which is being subducted beneath the Sunda Plate along the Sunda Trench, to the south of the islands. This is not a smooth process, as the rocks of the two plates constantly adhere together then break apart as the pressure builds up, causing Earthquakes. As the Australian Plate sinks further into the Earth it is partially melted by a combination of the friction and the heat from the planet's interior. Some of this melted material then rises through the overlying Sunda Plate, fueling the volcanoes of Java and Bali.

See also Seismic activity beneath Mount Tangkubanparahu, Indian Ocean shaken by a series of major Earthquakes, Massive Earthquake off Northern Sumatra, Large Earthquake in Northern Sumatra and and Earthquakes on Sciency Thoughts YouTube.

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Three new species of Chewing Lice from Limpopo Province, South Africa.

Chewing Lice are parasites living in the feathers of Birds (or occasionally the fur of Mammals). They are considered to be more primitive relatives of the more advanced blood-sucking lice; lacking the apparatus for sucking blood they either chew through the skin and lap blood from the resulting wound or simply eat the skin. The biodiversity of the group is not well studied, as the group has not been sampled in many parts of the world, and in many other places only studied on commercially important birds. Since it is likely that most Birds (and many Mammals) play host to unique Chewing Lice there are probably many more species than currently described.

In a paper published in the journal Zootaxa on 28 August 2012, Ali Halajian of the Department of Biodiversity (Zoology) at the University of Limpopo and the Department of Parasitology at the Faculty of Specialised Veterinary Sciences at the Science and Research Branch of the Islamic Azad University, and Oldrich Sychra of the Department of Biology and Wildlife Diseases at the Faculty of Veterinary Hygiene and Ecology at the University of Veterinary and Pharmaceutical Sciences in Brno in the Czech Republic, and Wilmien Luus-Powel and Derek Engelbrecht, also of the Department of Biodiversity (Zoology) at the University of Limpopo, describe three new species of Chewing Lice from Limpopo Province, South Africa, discovered by mist netting Pasarines (songbirds), then examining them carefully for Lice. All three new species are placed in the pre-existing genus Myrsidea.

The first new species is named Myrsidea aynazae, in honour of Ali Halajian's daughter Aynaz. The species is described from 13 individual Lice, found living on Yellow-streaked Greenbuls (Phyllastrephus flavostriatus) in the Woodbush Forest Reserve (roughly 300 km northeast of Pretoria).

The Yellow-streaked Greenbul (Phyllastrephus flavostriatus). Biodiversity Explorer/Izico Museums of Cape Town.

Myrsidea aynazae. (Top) Female. (Bottom) Male. Halajian et al. (2012).

The second new species is named Myrsidea eslamii, in honour of Ali Eslami, a veterinary parasitologist at the University of Tehran. The species is described from 15 individuals all collected from Orange Ground-Thrushes (Zoothera gurneyi) in the Woodbush Forest Reserve.

The Orange Ground-Thrush (Zoothera gurneyi). The Internet Bird Collection/Dubi Shapiro.

Myrsidea eslamii. (Top) Female. (Bottom) Male. Halajian et al. (2012).

The third new species of Chewing Louse is named Myrsidea mariquensis, after the Mariqua Flycatcher (Bradornis mariquensis), the Bird on which it was found. The species is named from three individuals found on Flycatchers in the Woodbush Forest Reserve.

The Mariqua Flycatcher (Bradornis mariquensis). The Internet Bird Collection/Robert Erasmus.

Myrsidea mariquensis. (Top) Female. (Bottom) Male. Halajian et al. (2012).

See also The impact of the introduced Common Myna on the Birds of Canberra, Three new species of Chewing Lice from Bulbuls in northern Vietnam and Giant Fleas from the Jurassic of China.

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Seismic activity beneath Mount Tangkubanparahu.

Mount Tangkubanparahu is a shield-like stratovolcano (cone-shaped volcano, with a low, broad profile) located on West Java to the north of Bandung, the former capitol of Indonesia. It is located on the western rim of the  6 × 8 km Sunda Caldera, the remains of a supervolcano thought to have been active 190 000 years ago. Tangkubanparahu itself rises to a height of 2084 m, and has undergone a number of small eruptions since the nineteenth century, though no major eruption has ever been observed; an eruption in May 1846 did cause some fatalities due to lahars (mudflows) and possibly small pyroclastic flows (avalanches of hot ash and gas). The last major eruption on Mount Tangkubanparahu is thought to have happened about 9500 years ago.

Satellite image of Mount Tangkubanparahu. Google Maps.

Between 13 and 23 August 2012 the Pusat Vulkanologi dan Mitigasi Bencana Geologi recorded an increase in seismic activity (small Earthquakes) beneath Tangkubanparahu, and visitors to the crater were banned as a precaution. Earthquakes beneath volcanoes can be a sign of magma moving in chambers under the visible cone, which can be a precursor to an eruption, although Tangkubanparahu has undergone at least four periods of raised seismicity since the last eruption, a small crater explosion in 1985. However this does not imply the tremors are completely safe; seismic activity on Tangkunbanparahu is often associated with fumaroles (gas emissions) which are typically high in toxic sulphur dioxide (SO₂). In September 2002 a number of dead animals were found near the summit after a series of minor tremors.

Java is located on the southern margin of the Sunda Plate. To the south of the island the Australian Plate is being subducted beneath this plate in the Sunda Trench, passing under the island and sinking into the Earth. As the plate is subducted it is partially melted by the friction and the heat of the planet's interior. Some of the melted material then rises through the overlying Sunda Plate, fueling the volcanoes of Java and neighboring Sumatra.

See also Indian Ocean shaken by a series of major Earthquakes, Massive Earthquake off Northern Sumatra, Large Earthquake in Northern Sumatra, Sumatra shaken by series of Earthquakes and Volcanoes on Sciency Thoughts YouTube.

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